This invention relates to electrical potentiometers and similar instruments. In particular, the invention relates to potentiometers and the like which are adjustable between a minimum and maximum resistance or to achieve other electrical circuit variations by the mechanical rotation of a driveable member. Most potentiometers can be classified as fractional turn, single turn or multi-turn types. Where a small potentiometer is desired as, for example, a trimmer potentiometer, it has been customary to use a fractional or single turn miniature potentiometer and by gearing or vernier techniques obtain small size characteristics. This has resulted in increased noise and decreased accuracy.
It is accordingly an object of the present invention to provide a miniaturized potentiometer or similar device which may be fractional, single or multi-turn, which is accurate, and which has low noise characteristics.
It is another object of the invention to provide a potentiometer or similar device which utilizes the direct drive of a ball on an annular resistance element or other element to vary the electrical resistance or other output provided by the device.
It is a further object of the present invention to provide a device of the type described which is capable of being programmed to provide any desired resistance function or other function, in a geometrical pattern such as spiral, elongation, triangulation, parabolic, logarithmic, linear, audio and like patterns.
It is a further object of the present invention to provide such a device wherein its resistance function can be easily changed by the insertion of a differently geometrically programmed grooved disc having a pattern as discussed above.
It is another object of the invention to provide a device which can be miniaturized and which is characterized by a high degree of accuracy, particularly in terms of repeatability.
Other objects and advantages of the invention will be apparent from the remaining portion of the specification.